Multiply by 11 Trick

How do you multiply a single-digit number by eleven?

• Write the number three times.

• Subtract the number from eleven.

• Write the number two times.

• Add the number to itself.

Tags

CCSS.3.NBT.A.3

What is the first step in multiplying a two-digit number by eleven?

• Copy the first digit of the number.

• Multiply the number by ten.

• Copy the last digit of the number.

• Add the two digits together.

What is the result of multiplying 17 by eleven?

• 207

• 197

• 177

• 187

Tags

CCSS.4.NBT.B.5

What is the result of 26 times eleven?

• 266

• 276

• 256

• 286

Tags

CCSS.4.NBT.B.5

What do you do if adding the digits of a two-digit number results in a number greater than 9?

• Restart the calculation.

• Carry over to the next digit.

• Subtract ten from the result.

• Ignore the carry.

Tags

CCSS.1.NBT.C.4

CCSS.2.NBT.B.5

How do you handle carrying over when the sum of two digits is more than 9?

• Add it to the next digit.

• Ignore it.

• Multiply it by the next digit.

• Subtract it from the next digit.

Tags

CCSS.1.NBT.C.4

CCSS.2.NBT.B.5

What is the result of 49 times eleven?

• 549

• 529

• 539

• 559

Tags

CCSS.4.NBT.B.5

What is the result of multiplying 123 by eleven?

• 1343

• 1363

• 1333

• 1353

Tags

CCSS.4.NBT.B.5

How do you multiply a three-digit number by eleven?

• Copy the first and last digits, then add the in-between numbers.

• Multiply each digit by eleven individually.

• Add all digits and place the sum in the middle.

• Divide the number by eleven first.

Tags

CCSS.5.NBT.B.6

CCSS.6.NS.B.2

Why does the trick for multiplying by eleven work?

• It's based on the distributive property of multiplication over addition.

• Due to the commutative property of multiplication.

• Because eleven is a prime number.

• Because of the properties of addition.

Tags

CCSS.4.NBT.B.5